Matrix-associated microbial communities in a nitrogen-removing on-site wastewater treatment system are largely structured by niche processes.

On-site wastewater treatment systems (OWTSs) can be designed to promote microbial communities with naturally occurring metabolic functions desirable to wastewater treatment. Among such OWTSs are nitrogen-removing biofilters (NRBs), comprising a sand layer overlying a sand-lignocellulose (sand-lc) layer and intended to promote sequential nitrification and denitrification. The design of NRBs is based on the hypothesis that niche processes like environmental selection strongly structure the microbial communities, which predicts that immigrating wastewater communities and matrix-associated communities will be distinct and that the matrix communities in the two layers will be distinct.

Three-dimensional mapping of mineral in intact shark centra with energy dispersive x-ray diffraction.

The centra of shark vertebrae consist of cartilage mineralized by a bioapatite similar to bone's carbonated hydroxyapatite, and, without a repair mechanism analogous to remodeling in bone, these structures still survive millions of cycles of high-strain loading. The main structures of the centrum are an hourglass-shaped double cone and the intermedialia which supports the cones. Little is known about the nanostructure of shark centra, specifically the relationship between bioapatite and cartilage fibers, and this study uses energy dispersive diffraction (EDD) with polychromatic synchrotron x-radiation to study the spatial organization of the mineral phase and its crystallographic texture.

Biochar application in biofiltration systems to remove nutrients, pathogens, and pharmaceutical and personal care products from wastewater.

Although conventional on-site wastewater treatment systems (OWTSs) provide only primary treatment of domestic wastewater, removal of a limited level of nutrients (N, P), pathogens, and pharmaceuticals and personal care products (PPCPs) could be achieved by such a treatment process. Biochar has the capacity to remove various contaminants and has been widely used as an ideal soil amendment in agriculture due to its persistence, superior nutrient-retention properties, low cost, and ready availability. However, few applications on the use of biochar in onsite wastewater treatment have been explored.

Elucidation of soil phosphorus speciation in mid-Atlantic soils using synchrotron-based microspectroscopic techniques.

Phosphorus deficiency and excess are concomitant problems in agricultural soils of the mid-Atlantic region. A fundamental understanding of soil P speciation is essential to assess P fate and transport in these soils. Current methods for soil P speciation often rely on sequential chemical extractions, which can introduce artifacts during analysis.

Intrinsic 3D Dynamic Surface Tracking based on Dynamic Ricci Flow and Teichmüller Map.

3D dynamic surface tracking is an important research problem and plays a vital role in many computer vision and medical imaging applications. However, it is still challenging to efficiently register surface sequences which has large deformations and strong noise. In this paper, we propose a novel automatic method for non-rigid 3D dynamic surface tracking with surface Ricci flow and Teichmüller map methods.

Human Computation in Visualization: Using Purpose Driven Games for Robust Evaluation of Visualization Algorithms.

Due to the inherent characteristics of the visualization process, most of the problems in this field have strong ties with human cognition and perception. This makes the human brain and sensory system the only truly appropriate evaluation platform for evaluating and fine-tuning a new visualization method or paradigm. However, getting humans to volunteer for these purposes has always been a significant obstacle, and thus this phase of the development process has traditionally formed a bottleneck, slowing down progress in visualization research.

Mammalian target of rapamycin and the kidney. II. Pathophysiology and therapeutic implications.

The mTOR pathway plays an important role in a number of common renal diseases, including acute kidney injury (AKI), diabetic nephropathy (DN), and polycystic kidney diseases (PKD). The activity of mTOR complex 1 (mTORC1) is necessary for renal regeneration and repair after AKI, and inhibition of mTORC1 by rapamycin has been shown to delay recovery from ischemic AKI in animal studies, and to prolong delayed graft function in humans who have received a kidney transplant. For this reason, administration of rapamycin should be delayed or discontinued in patients with AKI until full recovery of renal function has occurred.

Silencing of Mustn1 inhibits myogenic fusion and differentiation.

Mustn1 (Mustang, musculoskeletal temporally activated novel gene) was originally identified in fracture callus tissue, but its greatest expression is detected in skeletal muscle. Thus, we conducted experiments to investigate the expression and function of Mustn1 during myogenesis. Temporally, quantitative real-time PCR analysis of muscle samples from embryonic day 17 to 12 mo of age reveals that Mustn1 mRNA expression is greatest at 3 mo of age and beyond, consistent with the expression pattern of Myod.

Fast oscillatory rhythms in inspiratory motor discharge: a mathematical model.

In this paper, a mathematic model is applied to characterize spectral activity associated with fast oscillatory rhythms inherent in inspiratory discharges. Based on the estimated parameters, features are extracted to allow the model to discriminate between changes in the location, magnitude, and shape of spectral activities under basal conditions and during pharmacological blockade of gap junctions.

Hybrid automata as a unifying framework for modeling excitable cells.

We propose hybrid automata (HA) as a unifying framework for computational models of excitable cells. HA, which combine discrete transition graphs with continuous dynamics, can be naturally used to obtain a piecewise, possibly linear, approximation of a nonlinear excitable-cell model. We first show how HA can be used to efficiently capture the action-potential morphology--as well as reproduce typical excitable-cell characteristics such as refractoriness and restitution--of the dynamic Luo-Rudy model of a guinea-pig ventricular myocyte.

Inherent dispersion in restitution properties over space.

Cardiac tissue heterogeneities can result in spatially dependent restitution properties. We propose a method for quantifying the dispersed nature of these restitution curves (RCs) over a large number of imaged pixels/locations. Cardiac propagation in response to point stimulation was recorded in cardiomyocyte monolayers with voltage-sensitive dye over a large field of view using high resolution imaging.

A cycle-linear approach to modeling action potentials.

We introduce cycle-linear hybrid automata (CLHA) and show how they can be used to efficiently model dynamical systems that exhibit nonlinear, pseudo-periodic behavior. CLHA are based on the observation that such systems cycle through a fixed set of operating modes, although the dynamics and duration of each cycle may depend on certain computational aspects of past cycles. CLHA are constructed around these modes such that the per-cycle, per-mode dynamics are given by a time-invariant linear system of equations; the parameters of the system are dependent on a deformation coefficient computed at the beginning of each cycle as a function of memory units.

Efficient event-driven simulation of excitable hybrid automata.

We present an efficient, event-driven simulation framework for large-scale networks of excitable hybrid automata (EHA), a particular kind of hybrid automata that we use to model excitable cells. A key aspect of EHA is that they possess protected modes of operation in which they are non-responsive to external inputs. In such modes, our approach takes advantage of the analytical solution of the modes' linear differential equations to eliminate all integration steps, and therefore to dramatically reduce the amount of computation required.

Improvement of pulmonary hypoplasia associated with congenital diaphragmatic hernia by in utero CFTR gene therapy.

Congenital diaphragmatic hernia (CDH) may be an ideal candidate disease for in utero gene therapy as disrupted fetal lung growth plays a significant role in disease outcome. We previously demonstrated that transient in utero overexpression of CFTR during fetal development resulted in lung epithelial proliferation and differentiation. We hypothesized that gene therapy with CFTR would improve the pulmonary hypoplasia associated with congenital diaphragmatic hernia (CDH).

Adipocytes support cAMP-dependent translocation of aquaporin-2 from intracellular sites distinct from the insulin-responsive GLUT4 storage compartment.

Aquaporin-2 (AQP2), when expressed in fully differentiated 3T3-L1 adipocytes, displays cAMP-dependent plasma membrane translocation in a manner similar to its behavior in renal epithelial cells. The translocation of AQP2 required phosphorylation at serine 256, as the expression of AQP2/S256D was constitutively plasma membrane localized, whereas AQP2/S256A was refractory to forskolin stimulation. Unlike GLUT4, this property is not inhibited by depolymerization of cortical actin.